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Sounds very nice at idle. I'm not being critical here on the choice of mufflers, as I'm in need of replacing mine. I have Flowmaster 40's and no doubt you have read many post about drone between 2000 and 2500 rpm that seems typical with these and others. I love the sound of these at idle and had many compliments, but the drone zone is a killer!

Is there a possibility you can take that car out for drive to check for any drone in that rpm range. I'd be most interested in the findings. I have not seen the Flowmaster FX series, so yes I'm interested in the results and I'm sure others will be too.

Thanks,

Geoff.

 
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Looks like they did a good job, sounds good also

I used the Summit turbo mufflers and sounds great when stationary but yet to drive it

Be interesting if you get any drone as mentioned by Geoff

 
I drove the car last night and I didn't notice a drone. You always have a resonance with any dual system but nothing out of the ordinary. I have the exact same pipes and mufflers on my car with the exception that I have a set of electric cutouts installed also. Maybe I'm just used to the noise?? But there is nothing that is annoying or anything like that at any given rpm. Has a nice rumble to it out back, and quiet as a sewing machine up front.

Geoff, Does the exhaust system you have include an X pipe?? If not, I'm just wondering if that's where some of the drone sound maybe coming from on your car or are the 40's just known for it???

Not a T5, The rear valance is factory. Since this car came from the factory with a 2 barrel and single exhaust it got the standard rear valance. If the car would of came from the factory with dual exhaust then you would have the cutouts at the valance. But I think this looks goods. The guy did a nice job of tucking it up and maing a nice angled cut that matches the angle of the valance.

 
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Now to start tuning it properly. I do have a slight hesitation at mid throttle and its really rich at idle....... like burn your eyes in the garage rich. I'm going to start by checking and adjusting the floats first, then the idle air fuel mixture screws at all 4 corners with a vacuum gauge. I'm hoping those 2 adjustments should get me in the ballpark. I have initial timing set around 12* right now and it seems to like that.

Anyone else have any ideas being so rich at idle other than the two items above? I know if you don't have enough initial timing it can smell rich at idle, but at 12* I do not think that's the case.

 
Since I'm an Edelbrock guy, I'd say blame the Holley.   lollerz

Sounds awesome!  Well done!  ::thumb::

I'd also heard of the droning issue with the Flowmasters, but that's an interesting theory regarding the H-pipe vs. X-pipe.  I wouldn't have thought that it would make such a difference, but you can definitely tell the difference in sound characteristics between cars that have H-pipes and X-pipes.  H-pipes seem to have just a little bit more of a bass note sound than the X-pipes at idle.  I'm thinking it might have something to do with the exhaust flow slamming into and having to turn the corner when it hits the H-pipe junction, instead of just flowing together and pushing on down the pipes with the X-pipe configuration.  Having to suddenly change direction or having a smoother path would have an effect on the sound waves and vibrations of the exhaust system as well.  I could be all wrong on this, but I believe the H-pipe might actually cause just a tiny bit of turbulence in the exhaust flow - or maybe a little bit moreso than the X-pipe at the very least, with sound, gases, etc., all wrapped up in the mix and affected similarly - could be the difference.  I've noticed that most things involving repetitive motion tend to have a 'bad' spot somewhere that the balance is just a teeny bit off, which creates vibrations, noise, loss of efficiency, etc.,  Sound works similarly - when vibrations are tuned properly, the overall sound tends to smooth out and even decrease in volume somewhat, but if the soundwaves aren't in complete synch, the opposing secondary waves add to the volume and choppiness of the sound (I experience that effect every Tuesday night at Community Band rehearsal when the clarinets and saxophones don't feel the need to tune themselves before we start playing, which is quite annoying rofl ).

As for the drone, some mufflers are better than others at eliminating or minimizing the drone, which I would suspect has everything to do with the path the exhaust must take through the mufflers - they're basically just rat mazes inside, after all, with some having more insulation packed in than others.  Obviously, the less restrictive the muffler is, the louder it tends to be, since there is less insulating material and bends in the 'maze' for the exhaust flow to contend with.  Since the drone most likely has more to do with harmonics than simple noise, I don't think the mufflers really ever elminate it totally, but rather just dampen it to the point it's less noticeable.

OR - I could be totally off-base here and just talking out me arse.   :whistling:

 
Very good points Eric!  I also believe the muffler style has a lot to do with it. The 40 series are chambered mufflers and the flow fx are a straight through design. The sound waves bouncing around in the chambers maybe giving it that droning sound everyone complains of. The FX are a straight shot with packing around it. 





 
Kevin, thanks for your reply and input.

My car currently has an H pipe and 2 1/4" pipes with factory manifolds (M code car), but as I really need to replace the entire system, maybe a X pipe is the way to go. I'm not to familiar the physics of how resonance actually works, but I have worked on air induction resonators for cars. I mean I have a basic idea and from what little I know the H pipe connection is there to balance the flow between the two pies. What turbulence there is and how it reacts, I'm not sure.

Regardless in my car, even with all the sound deadening stuff I put in, the "drone" is ear splitting until I get past that rpm range, then it's just a good power sound.

That's why it's got to go and why this input is so helpful.

Thanks

Geoff.

 
Since I'm an Edelbrock guy, I'd say blame the Holley.   lollerz

Sounds awesome!  Well done!  ::thumb::

I'd also heard of the droning issue with the Flowmasters, but that's an interesting theory regarding the H-pipe vs. X-pipe.  I wouldn't have thought that it would make such a difference, but you can definitely tell the difference in sound characteristics between cars that have H-pipes and X-pipes.  H-pipes seem to have just a little bit more of a bass note sound than the X-pipes at idle.  I'm thinking it might have something to do with the exhaust flow slamming into and having to turn the corner when it hits the H-pipe junction, instead of just flowing together and pushing on down the pipes with the X-pipe configuration.  Having to suddenly change direction or having a smoother path would have an effect on the sound waves and vibrations of the exhaust system as well.  I could be all wrong on this, but I believe the H-pipe might actually cause just a tiny bit of turbulence in the exhaust flow - or maybe a little bit moreso than the X-pipe at the very least, with sound, gases, etc., all wrapped up in the mix and affected similarly - could be the difference.  I've noticed that most things involving repetitive motion tend to have a 'bad' spot somewhere that the balance is just a teeny bit off, which creates vibrations, noise, loss of efficiency, etc.,  Sound works similarly - when vibrations are tuned properly, the overall sound tends to smooth out and even decrease in volume somewhat, but if the soundwaves aren't in complete synch, the opposing secondary waves add to the volume and choppiness of the sound (I experience that effect every Tuesday night at Community Band rehearsal when the clarinets and saxophones don't feel the need to tune themselves before we start playing, which is quite annoying rofl ).

As for the drone, some mufflers are better than others at eliminating or minimizing the drone, which I would suspect has everything to do with the path the exhaust must take through the mufflers - they're basically just rat mazes inside, after all, with some having more insulation packed in than others.  Obviously, the less restrictive the muffler is, the louder it tends to be, since there is less insulating material and bends in the 'maze' for the exhaust flow to contend with.  Since the drone most likely has more to do with harmonics than simple noise, I don't think the mufflers really ever elminate it totally, but rather just dampen it to the point it's less noticeable.

OR - I could be totally off-base here and just talking out me arse.   :whistling:
Click to expand...
 Good input Eric, thanks.

Your last sentence, do you have any "Brit" in you? That's a so typical Brit expression and spelling!!

 
Kevin, thanks for your reply and input.

My car currently has an H pipe and 2 1/4" pipes with factory manifolds (M code car), but as I really need to replace the entire system, maybe a X pipe is the way to go. I'm not to familiar the physics of how resonance actually works, but I have worked on air induction resonators for cars. I mean I have a basic idea and from what little I know the H pipe connection is there to balance the flow between the two pies. What turbulence there is and how it reacts, I'm not sure.

Regardless in my car, even with all the sound deadening stuff I put in, the "drone" is ear splitting until I get past that rpm range, then it's just a good power sound.

That's why it's got to go and why this input is so helpful.

Thanks

Geoff.
Click to expand...
Geoff, I'm glad the info helped.  I can say without a doubt there is NO resonance that is even mildly earsplitting or annoying with this particular system! Just a nice V8 rumble.

 
turtle5353 pid='341891' dateline='1553094608']
Kevin, thanks for your reply and input.

My car currently has an H pipe and 2 1/4" pipes with factory manifolds (M code car), but as I really need to replace the entire system, maybe a X pipe is the way to go. I'm not to familiar the physics of how resonance actually works, but I have worked on air induction resonators for cars. I mean I have a basic idea and from what little I know the H pipe connection is there to balance the flow between the two pies. What turbulence there is and how it reacts, I'm not sure.

Regardless in my car, even with all the sound deadening stuff I put in, the "drone" is ear splitting until I get past that rpm range, then it's just a good power sound.

That's why it's got to go and why this input is so helpful.

Thanks

Geoff.
Click to expand...
Geoff, I'm glad the info helped.  I can say without a doubt there is NO resonance that is even mildly earsplitting or annoying with this particular system! Just a nice V8 rumble.
Click to expand...
 Kevin, that great news.

 For those interested and yes, probably should start this in a new post, but while we're here, I looked up the Flowmaster Fx series. I found a web site,  There is some good info there with a YouTube video. From there I found a Summit video from Flowmaster, "how to select he right flowmaster muffler for your vehicle"

Though it might be good info for all. Interestingly, the guy in the video says the Flowmaster Delta 50, although longer at 17" will give that nice note, but greatly reduced drone in the cabin, so that might be another consideration.

One thing leads to another I guess!

Geoff.

EDIT< something wrong with the link, I typed it as it showed, but not fully working. Hmmm, I'll check and get back.

Ok this should work now, copied directly.

 
Last edited by a moderator:
Since I'm an Edelbrock guy, I'd say blame the Holley.   lollerz

Sounds awesome!  Well done!  ::thumb::

I'd also heard of the droning issue with the Flowmasters, but that's an interesting theory regarding the H-pipe vs. X-pipe.  I wouldn't have thought that it would make such a difference, but you can definitely tell the difference in sound characteristics between cars that have H-pipes and X-pipes.  H-pipes seem to have just a little bit more of a bass note sound than the X-pipes at idle.  I'm thinking it might have something to do with the exhaust flow slamming into and having to turn the corner when it hits the H-pipe junction, instead of just flowing together and pushing on down the pipes with the X-pipe configuration.  Having to suddenly change direction or having a smoother path would have an effect on the sound waves and vibrations of the exhaust system as well.  I could be all wrong on this, but I believe the H-pipe might actually cause just a tiny bit of turbulence in the exhaust flow - or maybe a little bit moreso than the X-pipe at the very least, with sound, gases, etc., all wrapped up in the mix and affected similarly - could be the difference.  I've noticed that most things involving repetitive motion tend to have a 'bad' spot somewhere that the balance is just a teeny bit off, which creates vibrations, noise, loss of efficiency, etc.,  Sound works similarly - when vibrations are tuned properly, the overall sound tends to smooth out and even decrease in volume somewhat, but if the soundwaves aren't in complete synch, the opposing secondary waves add to the volume and choppiness of the sound (I experience that effect every Tuesday night at Community Band rehearsal when the clarinets and saxophones don't feel the need to tune themselves before we start playing, which is quite annoying rofl ).

As for the drone, some mufflers are better than others at eliminating or minimizing the drone, which I would suspect has everything to do with the path the exhaust must take through the mufflers - they're basically just rat mazes inside, after all, with some having more insulation packed in than others.  Obviously, the less restrictive the muffler is, the louder it tends to be, since there is less insulating material and bends in the 'maze' for the exhaust flow to contend with.  Since the drone most likely has more to do with harmonics than simple noise, I don't think the mufflers really ever elminate it totally, but rather just dampen it to the point it's less noticeable.

OR - I could be totally off-base here and just talking out me arse.   :whistling:
Click to expand...
 Good input Eric, thanks.

Your last sentence, do you have any "Brit" in you? That's a so typical Brit expression and spelling!!
Click to expand...
No - nothing like that.  I do interface with with some Brits, Scots, and Aussies now and then on the various forums here and there, but I'm actually half-Danish (father's side) and American Mutt (Mom's) for the most part.  I've also got a lot of experiece on what passes thru online language filters and what might not. ;)

 
Since I'm an Edelbrock guy, I'd say blame the Holley.   lollerz

Sounds awesome!  Well done!  ::thumb::
Click to expand...
 Good input Eric, thanks.

Your last sentence, do you have any "Brit" in you? That's a so typical Brit expression and spelling!!
Click to expand...
No - nothing like that.  I do interface with some Brits, Scots, and Aussies now and then on the various forums here and there, but I'm actually half-Danish (father's side) and American Mutt (Mom's) for the most part.  I've also got a lot of experiece on what passes thru online language filters and what might not. ;)
Click to expand...
 Ah! I see. I don't often see Americans spell "ass" as arse. But then American spelling gets me all the time, but I'm learning how to spell the lazy way!! lol. Okay, simplified.

 

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